BELFAST, Maine — Local police are warning residents to be wary about a new scam that seems to be targeting people who are living on the financial edge.

Belfast Police Chief Mike McFadden said several times so far this winter, people in the city have fallen for the so-called “Green Dot” card scam. In that one, scammers call a person claiming to be from a major service provider, such as Central Maine Power, and tell the consumer that they are behind on their payments.

“If you don’t make a payment within the next hour, your service will be shut off,” the scam caller says, according to McFadden. The chief added, “If it’s 5 below zero and 6 p.m., and you think CMP is going to shut your power off, you pay attention.”

At that point, the customer is instructed by the telephone caller to go buy a “Green Dot,” or prepaid debit card, put a substantial sum of money on it and call back with the card number.

“It’s a hugely successful scam,” McFadden said. “It’s very simple.”

He wants to make sure people know that legitimate service providers would not make such calls and demands.

“If you haven’t received late notices in the mail or telephone calls from CMP reminding you your bill hasn’t been paid, don’t question yourself,” he said. “CMP will work with you. And before you do anything, call the company directly.”